It is already known to use stretchable foils for the packaging of fruit or vegetables which are situated in containers of dish form. These foil sections, drawn from a supply roll and cut to the desired length, are stretched over the top of the filled dish. Then the dish is lifted on a lifting table and the foil edges are folded around the underside of the bottom of the dish and there adhered to one another by the action of heat.
The stretch foil, consisting of a soft synthetic plastic material must be very thin for this purpose so that it can adapt itself well to the articles with irregular surface to be packed, and nevertheless causes no pressure points on the packed material. Fruit, for example, is especially sensitive to this respect. On the other hand, the processing of such foils in packaging machines involves considerable difficulties on account of their softness, easy stretchability and deformability, and necessitates considerable machinery expense in order to avoid both tearing and undesired folding of the thin foil.